App install through GP and cmd shell

Hello,

I am attempting to install an application through group policy.  Actually, I am attempting to upgrade an application that is already installed through GP.  I have the .cmd file that was used to install the application.  It looks for an existing file on the user's C drive and either installs or does nothing depending on whether the file exists or not.  If the file exists it means the application is already installed.  The problem with the upgrade is that there is no discernable indicator to point to after the upgrade to tell the .cmd file that the program is upgraded.  There's no registry indicators and no difference in the install directory.  What I have in mind is to create a small text file with the upgrade on the user's C drive and have the .cmd file look for that to determine whether to run the upgrade or not.  I cannot figure out how to create a simple text file on the user's C drive through the .cmd file.  I will attach the existing .cmd file so you can see what I have and hopefully we can come up with an easy way to do this.

Thanks,
Cheese
centennial.cmd